President George Bush faces a damaging political firestorm on the eve of the vital mid-term elections after it emerged yesterday that an influential military newspaper is to call for the resignation of his Defence Secretary, Donald Rumsfeld.

The call could not come at a worse time for Bush and the Republican party as they brace for a widely predicted defeat in Tuesday's elections that could see the Democrats capture both Houses of Congress.

Now it has been revealed that the Military Times Media Group, which publishes the army newspaper The Army Times, is to print an anti-Rumsfeld editorial tomorrow.

'Regardless of which party wins [the mid-term elections on 7 November] the time has come, Mr President, to face the hard bruising truth: Donald Rumsfeld must go,' it will conclude.

The editorial criticises Rumsfeld for being out of touch both with top military figures and a US public that is increasingly anti-war. 'His strategy has failed, and his ability to lead is compromised. And although the blame for our failures in Iraq rests with the Secretary, it will be the troops who bear its brunt,' the editorial will say.

Its timing is likely to damage Republican credibility on Iraq even further just 24 hours before Americans go to the polls. It comes after Bush publicly backed Rumsfeld last week and praised the Defence Secretary for doing a great job.

The news adds to a sense of unravelling among senior Republicans, many of whom supported the invasion of Iraq but are now disassociating themselves from the way the war has been waged. Several leading conservatives have given interviews to Vanity Fair magazine criticising the Bush administration's Iraq policy, labelling it a disaster.

They included Richard Perle, who chaired a committee of Pentagon policy advisers early in Bush's administration, and Kenneth Adelman, who served on the Defence Policy Board.

A Newsweek poll released yesterday struck a further blow to Republican hopes. It showed that 54 per cent of voters likely to turn out would support the Democrats, compared with just 38 per cent backing the Republicans. Among vital independent voters, the gap was even wider: just 26 per cent backed the Republicans and 51 per cent the Democrats.

The Republicans are also dealing with the fallout from a sex scandal involving an evangelical church leader linked to Bush. Ted Haggard of the New Life Church in Colorado has been forced to resign after being accused of having sex with a male prostitute and using the drug crystal meth. The church's independent investigative board found him guilty of 'sexually immoral conduct'.